I remember seeing these advertised either by Navy Arms or EMF in Shotgun News as early as the mid 1970's. I have some old Navy catalogs and some Shotgun News packed in a box somewhere in storage, but have no idea where to start looking.
Anyway, going from memory----At the time Uberti had only offered the 66 in .38 spl. and .44-40. I seem to remember that even 45 LC was not available at the time.
Anyway, Uberti came out with the 22 cal to try to appeal to a broader or younger audience, but unfortunately at $350 to $400 a pop they were a bit expensive for that caliber. One could buy a nice new Winchester lever action 9422 for about $125 to $150 at the time and Ruger 10/22's were all the rage.
Consequently they only offered them for a short while, and I can also remember seeing them offered in Shotgun New on close out much later, but even at a reduced price they were more than standard 22's of the day.
Because of this they are a bit rare and usually command premium price today. The only negative I have ever heard is that since the basic brass frame is the same as the larger calibers, the guns are a bit on the heavy side for a 22, but I've also heard that they are still fun to shoot.
Congrats